diff --git a/Mailman/Gui/General.py b/Mailman/Gui/General.py

index 980e5f2..dfde630 100644

--- a/Mailman/Gui/General.py

+++ b/Mailman/Gui/General.py

@@ -559,6 +559,14 @@ mlist.info.

                                           or not isinstance(val, IntType)):

             doc.addError(_("""admin_member_chunksize attribute not

             changed!  It must be an integer > 0."""))

+        elif property == 'host_name':

+            try:

+                Utils.ValidateEmail('user@' + val)

+            except Errors.EmailAddressError:

+                doc.addError(_("""host_name attribute not changed!

+                It must be a valid domain name."""))

+            else:

+                GUIBase._setValue(self, mlist, property, val, doc)

         else:

             GUIBase._setValue(self, mlist, property, val, doc)

diff --git a/Mailman/Utils.py b/Mailman/Utils.py

index 9dbd0b5..fd6ac79 100644

--- a/Mailman/Utils.py

+++ b/Mailman/Utils.py

@@ -1019,6 +1019,7 @@ _badwords = [

     '

     '

     '

+    '@keyframes',

     r'\bj(?:ava)?script\b',

     r'\bvbs(?:cript)?\b',

     r'\bdomactivate\b',

@@ -1035,12 +1036,14 @@ _badwords = [

     r'\bon(?:de)?activate\b',

     r'\bon(?:after|before)print\b',

     r'\bon(?:after|before)update\b',

+    r'\b(?:on)?animation(?:end|iteration|start)\b',

     r'\bonbefore(?:(?:de)?activate|copy|cut|editfocus|paste)\b',

     r'\bonbeforeunload\b',

     r'\bonbegin\b',

     r'\bonblur\b',

     r'\bonbounce\b',

     r'\bonbroadcast\b',

+    r'\boncanplay(?:through)?\b',

     r'\bon(?:cell)?change\b',

     r'\boncheckboxstatechange\b',

     r'\bon(?:dbl)?click\b',

@@ -1056,7 +1059,9 @@ _badwords = [

     r'\bondrag(?:drop|end|enter|exit|gesture|leave|over)?\b',

     r'\bondragstart\b',

     r'\bondrop\b',

-    r'\bonend\b',

+    r'\bondurationchange\b',

+    r'\bonemptied\b',

+    r'\bonend(?:ed)?\b',

     r'\bonerror(?:update)?\b',

     r'\bonfilterchange\b',

     r'\bonfinish\b',

@@ -1066,21 +1071,28 @@ _badwords = [

     r'\bonkey(?:up|down|press)\b',

     r'\bonlayoutcomplete\b',

     r'\bon(?:un)?load\b',

+    r'\bonloaded(?:meta)?data\b',

+    r'\bonloadstart\b',

     r'\bonlosecapture\b',

     r'\bonmedia(?:complete|error)\b',

+    r'\bonmessage\b',

     r'\bonmouse(?:down|enter|leave|move|out|over|up|wheel)\b',

     r'\bonmove(?:end|start)?\b',

     r'\bon(?:off|on)line\b',

+    r'\bonopen\b',

     r'\bonoutofsync\b',

     r'\bonoverflow(?:changed)?\b',

     r'\bonpage(?:hide|show)\b',

     r'\bonpaint\b',

     r'\bonpaste\b',

     r'\bonpause\b',

+    r'\bonplay(?:ing)?\b',

+    r'\bonpopstate\b',

     r'\bonpopup(?:hidden|hiding|showing|shown)\b',

     r'\bonprogress\b',

     r'\bonpropertychange\b',

     r'\bonradiostatechange\b',

+    r'\bonratechange\b',

     r'\bonreadystatechange\b',

     r'\bonrepeat\b',

     r'\bonreset\b',

@@ -1090,19 +1102,30 @@ _badwords = [

     r'\bonrow(?:delete|enter|exit|inserted)\b',

     r'\bonrows(?:delete|enter|inserted)\b',

     r'\bonscroll\b',

-    r'\bonseek\b',

+    r'\bonsearch\b',

+    r'\bonseek(?:ed|ing)?\b',

     r'\bonselect(?:start)?\b',

     r'\bonselectionchange\b',

+    r'\bonshow\b',

     r'\bonstart\b',

+    r'\bonstalled\b',

     r'\bonstop\b',

+    r'\bonstorage\b',

     r'\bonsubmit\b',

+    r'\bonsuspend\b',

     r'\bonsync(?:from|to)preference\b',

     r'\bonsyncrestored\b',

     r'\bontext\b',

-    r'\bontimeerror\b',

+    r'\bontime(?:error|update)\b',

+    r'\bontoggle\b',

+    r'\bontouch(?:cancel|end|move|start)\b',

     r'\bontrackchange\b',

+    r'\b(?:on)?transitionend\b',

     r'\bonunderflow\b',

     r'\bonurlflip\b',

+    r'\bonvolumechange\b',

+    r'\bonwaiting\b',

+    r'\bonwheel\b',

     r'\bseeksegmenttime\b',

     r'\bsvgabort\b',

     r'\bsvgerror\b',

diff --git a/Mailman/Gui/GUIBase.py b/Mailman/Gui/GUIBase.py

index a365aca..290f614 100644

--- a/Mailman/Gui/GUIBase.py

+++ b/Mailman/Gui/GUIBase.py

@@ -169,6 +169,7 @@ class GUIBase:

                 doc.addError(_('Invalid value for variable: %(property)s'))

             # This is the parent of MMBadEmailError and MMHostileAddress

             except Errors.EmailAddressError:

+                error = Utils.websafe(str(error))

                 doc.addError(

                     _('Bad email address for option %(property)s: %(val)s'))

             else: